REAGENT or RESOURCE	SOURCE	IDENTIFIER
Bacterial and Virus Strains
BL21(DE3)	Novagen	Cat# 69450
Rosetta 2(DE3)	Novagen	Cat# 71400
Chemicals, Peptides, and Recombinant Proteins
λ phage protein phosphatase (λPPase), His6-tagged	This work	N/A
HRV14 3C protease, His6SUMO-tagged	This work	N/A
CDC7-DBF4 heterodimers (WT and mutants)	This work and Hughes et al. (2012)	N/A
ATPγS-S40-MCM2(33-47) bisubstrate peptide	This work	N/A
biotinylated MCM2(35-47) peptides (WT and mutants)	This work	N/A
ATPγS	Merck	Cat# 119120
Rink Amide resin	Merck	Cat# 855120
Fmoc-Dpr(Mtt)-OH	Merck	Cat# 852089
Critical Commercial Assays
SAM2 biotin-capture membrane assay	Promega	Cat# V2861
Deposited Data
Initial model used for molecular replacement	Hughes et al. (2012)	PDB: 4F9C
Structure of a pCDK2/CyclinA transition-state mimic	Bao et al. (2011)	PDB: 3QHW
CDC7-DBF4 heterodimer in complex with XL413	This work	PDB: 6YA6
CDC7-DBF4 bound to ADP-BeF3-	This work	PDB: 6YA7
CDC7-DBF4 bound to bisubstrate peptide	This work	PDB: 6YA8
Oligonucleotides
Forward primer λPPase 5′-TGCGCTATTACGAAAAAATTGATGG	Sigma-Aldrich	N/A
Reverse primer λPPase 5′-GCGCGTCGACTGCGCCTTCTC CCTGTACC	Sigma-Aldrich	N/A
Forward primer HRV14 3C 5′-GGACGAATTCGGACCAAACACAGA ATTTGCAC	Sigma-Aldrich	N/A
Reverse primer HRV14 3C 5′-GGAGCCTCGAGTTATTGTTTCTCTAC AAAATATTG	Sigma-Aldrich	N/A
Recombinant DNA
pET-λPPase-His6	This work	N/A
pETSUMO-3C	This work	N/A
pRSFDuet1	Novagen	Cat# 71341
pCDFDuet1	Novagen	Cat# 71340
pRSFDuet-CDC7 (WT and mutants)	This work and Hughes et al. (2012)<	N/A
Software and Algorithms
XDS	Kabsch (2010)	http://xds.mpimf-heidelberg.mpg.de/
SCALA	Evans (2006)	http://www.ccp4.ac.uk/html/scala.html
Xia2	Winter et al. (2013)	https://xia2.github.io/
Phaser	McCoy et al. (2007)	http://www.ccp4.ac.uk/html/phaser.html
Phenix Autobuild	Terwilliger et al. (2008)	https://www.phenix-online.org/
phenix.refine	Adams et al. (2010)	https://www.phenix-online.org/
Refmac	Murshudov et al. (1997)	http://www.ccp4.ac.uk/html/refmac5.html
Coot	Emsley and Cowtan (2004)	https://www2.mrc-lmb.cam.ac.uk/personal/pemsley/coot/
MolProbity	Williams et al. (2018)	http://molprobity.biochem.duke.edu/
PyMOL	Warren L. DeLano and Schrödinger LLC	https://pymol.org